Adropin: A New Marker for Predicting Late Saphenous Vein Graft Disease after Coronary Artery Bypass Grafting

Current Knowledge of Selected Cardiovascular Biomarkers in Pediatrics: Kidney Injury Molecule-1, Salusin-α and -β, Uromodulin, and Adropin

Cardiovascular diseases are the leading cause of morbidity and mortality in the modern world. Their common denominator is atherosclerosis, a process beginning in childhood. In pediatrics, the aim of preventive measures is to recognize children and adolescents at risk for accelerated atherosclerosis and possible premature cardiovascular events in adulthood. Several diagnostic procedures and biomarkers are available for cardiovascular risk assessment in adults. However, reliable markers in pediatrics are still insufficiently studied. In this contribution, we discuss five potential biomarkers of particular interest: kidney injury molecule-1, salusin-α and -β, uromodulin, and adropin. Studies regarding the pediatric population are scarce, but they support the evidence from studies in the adult population. These markers might entail both a prognostic and a therapeutic interest.

Serum irisin and adropin levels may be predictors for coronary artery ectasia

BACKGROUND

There is strong evidence that oxidative stress and inflammation may contribute to the coronary artery ectasia (CAE) pathophysiology. Recent studies have shown that serum irisin and adropin levels are associated with oxidative stress and inflammation. In the light of this information, we aimed to investigate the possible relationship between serum irisin, adropin levels and CAE.

PATIENTS & METHODS

A total of 50 consecutive patients with CAE and 50 consecutive patients with normal coronary anatomy (NCA) were enrolled into the study. Serum irisin, adropin and other clinical parameters were compared between groups.

RESULTS

Adropin (p < .001) and irisin (p < .001) levels were lower in the CAE group. Low adropin (p = .014) and irisin (p < .001) levels were detected as an independent risk factor for CAE in multiple regression analysis. Receiver operating characteristic curve analysis showed that serum adropin (p < .001) and irisin (p < .001) leves was significant predictor of CAE.

CONCLUSIONS

The results of this study showed that serum irisin and adropin level was lower in the CAE group than in the NCA group. Irisin and adropin could play a role in the pathogenesis of CAE.

PLCL vascular external sheath carrying prednisone for improving patency rate of the vein graft

Coronary artery bypass graft surgery (CABG) is an impactful treatment for coronary heart disease. Intimal hyperplasia is the central reason for the restenosis of vein grafts after CABG. The introduction of external vascular sheaths around VGs (VGs) can effectively inhibit intimal hyperplasia and ensure the patency of VGs. In this study, the well-known biodegradable copolymer poly (ε-caprolactone-co-L, L-lactide) (PLCL) was electrospun into high porosity external sheaths. The prednisone loaded in the PLCL sheath was slowly released during the degradation process of PLCL. Under the combined effects of sheath and prednisone, intimal hyperplasia was inhibited. For the cell experiments, all sheaths show low cytotoxicity to L929 cells at different concentrations at different time intervals. The ultrasonography and histological results showed prominent dilation and intimal hyperplasia of VG without sheath after two months of surgery. But there was no dilation in PLCL and PLCL_Prednisone groups. Notably, the prednisone-loaded sheath group exhibited efficacy in inhibiting intimal hyperplasia and ensured graft patency.

Adropin as a potential mediator of the metabolic system-autonomic nervous system-chronobiology axis: Implementing a personalized signature-based platform for chronotherapy

Adropin is a peptide hormone, which plays a role in energy homeostasis and controls glucose and fatty acid metabolism. Its levels correlate with changes in carbohydrate-lipid metabolism, metabolic diseases, central nervous system function, endothelial function and cardiovascular disease. Both metabolic pathways and adropin are regulated by the circadian clocks. Here, we review the roles of the autonomic nervous system and circadian rhythms in regulating metabolic pathways and energy homeostasis. The beneficial effects of chronotherapy in various systems are discussed. We suggest a potential role for adropin as a mediator of the metabolic system-autonomic nervous system axis. We discuss the possibility of establishing an individualized adropin and circadian rhythm-based platform for implementing chronotherapy, and variability signatures for improving the efficacy of adropin-based therapies are discussed.

Adropin as A Fat-Burning Hormone with Multiple Functions-Review of a Decade of Research

Adropin is a unique hormone encoded by the energy homeostasis-associated (Enho) gene. Adropin is produced in the liver and brain, and also in peripheral tissues such as in the heart and gastrointestinal tract. Furthermore, adropin is present in the circulatory system. A decade after its discovery, there is evidence that adropin may contribute to body weight regulation, glucose and lipid homeostasis, and cardiovascular system functions. In this review, we summarize and discuss the physiological, metabolic, and pathophysiological factors regulating Enho as well as adropin. Furthermore, we review the literature addressing the role of adropin in adiposity and type 2 diabetes. Finally, we elaborate on the role of adropin in the context of the cardiovascular system, liver diseases, and cancer.

Prediction of Major Adverse Cardiovascular Events and Slow/No-Reflow by Virtual Histology Imaging After Percutaneous Interventions on Saphenous Vein Grafts

Saphenous vein grafts disease (SVGD) is a common complication after coronary artery bypass graft (CABG) and usually treated by percutaneous coronary intervention (PCI). In this prospective cohort study, we performed virtual histology-intravascular ultrasound to investigate whether plaque composition and morphological characteristics were associated with post-PCI major adverse cardiac events (MACEs) and slow/no-reflow in patients with SVGD. Patients (n = 90) were studied (76.7% men, mean age 64.9 ± 8.2 years and mean duration of SVG 8.0 ± 3.6 years). There were 77.8% lesions with a plaque burden of at least 70%; 18 MACE incidences accumulated in 14 patients over 12 months post-PCI and slow/no-reflow was observed in 12 patients. On adjusted multivariate analysis, lesion length (hazard ratio [HR] = 1.05; 95% confidence interval [CI]: 1.01-1.08]); age of CABG (HR = 1.51 [95% CI: 1.11-2.05], and absolute necrotic core (NC) area (HR = 8.04 [95% CI: 1.86-34.73]) were independently associated with MACEs. Factors independently associated with slow/no-reflow post-PCI were preprocedure systolic blood pressure (odds ratio [OR] = 0.98; 95% CI: 0.96-0.99) and absolute NC area (OR = 2.47 (95% CI: 1.14-5.36). A cutoff value of absolute NC area at ≥1.1 mm² may serve as a significant risk predictor for no-reflow after SVG-PCI. Factors associated with MACEs and the slow/no-reflow phenomenon following PCI of the SVG can be used in risk assessment of SVG.

Negative association between serum adropin and hypertensive disorders complicating pregnancy

Objective: Study the association of adropin and hypertensive disorders complicating pregnancy (HDCP). Methods: Patients with HDCP were matched with normotensive women (47 pairs). Adropin concentrations were detected by enzyme-linked immunosorbent assay. Results: Compared with the controls, the serum adropin levels were lower in the HDCP group (P < 0.001) and in HDCP subgroups (gestational hypertension, mild preeclampisa, and severe preeclampsia, term, preterm, early onset, and late onset) (all P < 0.05). After adjustment for confounders, adropin remained negatively associated with HDCP (P = 0.027). Conclusion: Lower adropin concentration is significantly associated with HDCP, suggesting that higher or normal adropin levels may be protective against HDCP.

Application of virtual histological intravascular ultrasound in plaque composition assessment of saphenous vein graft diseases

OBJECTIVE

Saphenous vein grafts disease (SVGD) is a common complication after coronary artery bypass graft (CABG) and normally treated by percutaneous coronary intervention (PCI). The most common complication after SVG-PCI is slow or no-reflow. It is known that the no-reflow phenomenon occurs in up to 15% of the SVG-PCI and is associated with high risk of major adverse cardiac events (MACEs) and mortality, therefore, it is important to investigate the factors that could predict the clinical outcome of PCI for risk stratification and guiding interventions. In recent years, the spectral analysis of intravascular ultrasound (IVUS) radiofrequency data (virtual histology-IVUS [VH-IVUS]) has been used to provide quantitative assessment on both plaque compositions and morphologic characteristics.

DATA SOURCES

The PubMed, Embase, and Central databases were searched for possible relevant studies published from 1997 to 2018 using the following index keywords: "Coronary artery bypass grafting," "Saphenous venous graft disease," "Virtual histology-intravascular ultrasound," "Virtual histology-intravascular ultrasound," and "Percutaneous coronary intervention."

STUDY SELECTION

The primary references were Chinese and English articles including original studies and literature reviews, were identified and reviewed to summarize the advances in the application of VH-IVUS techniques in situ vascular and venous graft vascular lesions.

RESULTS

With different plaque components exhibiting a defined spectrum, VH-IVUS can classify atherosclerotic plaque into four types: fibrous tissue (FT), fibro fatty (FF), necrotic core (NC), and dense calcium (DC). The radiofrequency signal is mathematically transformed into a color-coded representation, including lipid, fibrous tissue, calcification, and necrotic core. Several studies have demonstrated the independent relationship between VH-IVUS-defined plaque classification or plaque composition and MACEs, but a significant association between plaque components and no-reflow after PCI in acute coronary syndrome. In recent years, VH-IVUS are applied to assess the plaque composition of SVGD, based on the similarity of pathophysiological mechanisms between coronary artery disease (CAD) and SVGD, further studies with the larger sample size, the long-term follow-up, multicenter clinical trials may be warranted to investigate the relationship between plaque composition of saphenous vein graft (SVG) by VH-IVUS and clinical outcomes in patients with SVGD undergoing PCI.

CONCLUSIONS

In degenerative SVG lesions, VH-IVUS found that plaque composition was associated with clinical features, future studies need to explore the relationship between VH-IVUS defined atherosclerotic plaque components and clinical outcomes in SVGD patients undergoing PCI, an innovative prediction tool of clinical outcomes can be created.

Relationship between plaque composition by virtual histology intravascular ultrasound and clinical outcomes after percutaneous coronary intervention in saphenous vein graft disease patients: study protocol of a prospective cohort study

Background

Plaque composition and morphologic characteristics identified by virtual histology intravascular ultrasound (VH-IVUS) can determine plaques at increased risk of clinical events following percutaneous coronary intervention (PCI) among coronary artery disease (CAD) patients. However, there have been few studies to investigate the relationship between plaque composition of saphenous vein graft (SVG) by VH-IVUS and clinical outcomes in patients with saphenous vein graft disease (SVGD) undergoing PCI. The purpose of this study is to determine whether plaque components and characteristics by VH-IVUS can predict major adverse cardiac events (MACEs) among SVGD patients undergoing PCI.

Methods/design

This is a prospective cohort study conducted in Tianjin Chest Hospital, China. Participants with SVGD referred for PCI will be invited to participate in this study, and will be followed up at 1, 6, 12, 24 and 36 months post-PCI to assess clinical outcomes.

The planned sample size is 175 subjects. We will recruit subjects with SVGD scheduled to receive PCI, aged 18–80 years, with a history of previous coronary artery bypass graft (CABG) surgery more than 1 year ago, and willing to participate in the study and sign informed consent.

The composite primary study endpoint is the incidence of MACEs after PCI for SVGD, including death from cardiac causes, non-fatal myocardial infarction, unplanned target lesion revascularization (TLR) and target vessel revascularization (TVR). The primary outcome analysis will be presented as Kaplan-Meier estimates and the primary outcome analysis will be carried out using a Cox proportional hazards regression model.

Discussion

Once the predictive values of plaque components and characteristics by VH-IVUS on subsequent clinical outcomes are determined among SVGD patients undergoing PCI, an innovative prediction tool of clinical outcomes for SVGD patients undergoing PCI will be created, which may lead to the development of new methods of risk stratification and intervention guidance.

Trial registration

The study is registered to ClinicalTrials.gov (NCT03175952).

Review of risk factors, treatment, and prevention of saphenous vein graft disease after coronary artery bypass grafting

Saphenous vein graft disease (SVGD) is a type of vascular disease that may develop after coronary artery bypass grafting (CABG). SVGD seriously affects the short-term and long-term effects of CABG and increases the incidence of major adverse cardiovascular events. It is very important to identify patients at greatest risk and carry out prevention and treatment measures to determine the risk factors for SVGD. Many factors contribute to SVGD when the vein is grafted into an arterial environment, such as surgery-related factors, smoking, diabetes mellitus, hyperlipidemia, and others. In this review, we discuss the risk factors for SVGD, current surgical and pharmacologic therapies with which to manage SVGD, and the prevention of SVGD.

Association between serum adropin level and burden of coronary artery disease in patients with non-ST elevation myocardial infarction

Objective:

Previous studies revealed the relationship between stable coronary artery disease (CAD) and serum adropin level, but this relationship has not been investigated in patients with non-ST segment elevation myocardial infarction (NSTEMI). The present study is an analysis of the relationship between adropin and severity of CAD assessed based on SYNTAX score in patients with NSTEMI.

Methods:

A total of 109 participants, 80 patients with NSTEMI and 29 healthy individuals, were prospectively enrolled in the study. Patients with NSTEMI were divided to 2 groups: high SYNTAX score (≥32) (35 patients) and low SYNTAX score (<32) (45 patients). Adropin level was measured from blood serum samples using enzyme-linked immunosorbent assay test.

Results:

Patients with NSTEMI and high SYNTAX score had significantly lower serum adropin level (2357.30 pg/mL±821.58) compared to NSTEMI patients with low SYNTAX score (3077.00 pg/mL±912.86) and control group (3688.00±956.65). Adropin cut-off value for predicting high SYNTAX score on receiver-operating characteristic curve analysis was determined to be 2759 pg/mL, with a sensitivity of 63% and a specificity of 57%. Adropin was an independent predictor for high SYNTAX score (odds ratio=0.999; 95% confidence interval: 0.998–1.000; p=0.007).

Conclusion:

Adropin could be an alternative blood sample value for predicting severity of CAD.

Salusins and adropin: New peptides potentially involved in lipid metabolism and atherosclerosis

Dyslipidemia is one of the most potent risk factors for the development of atherosclerosis. The high atherosclerotic risk in dyslipidemic patients is associated with endothelial dysfunction. During the last two decades, novel bioactive peptides have emerged as potential biomarkers of endothelial dysfunction and dyslipidemia-salusins and adropin. Salusin-alpha is likely to prevent atherosclerosis, while salusin-beta may act as a potential proatherogenic factor. Adropin was recently identified as important for energy homeostasis and lipid metabolism. Adropin is closely related to the inhibition of atherosclerosis by up-regulation of the endothelial nitric oxide synthase expression through the vascular endothelial growth factor receptor-2. These peptides represent a novel target to limit diseases characterized by endothelial dysfunction and may form the basis for the development of new therapeutic agents for treating metabolic disorders associated with atherosclerosis.

Inverse association between carbohydrate consumption and plasma adropin concentrations in humans

OBJECTIVE

The role of metabolic condition and diet in regulating circulating levels of adropin, a peptide hormone linked to cardiometabolic control, is not well understood. In this study, weight loss and diet effects on plasma adropin concentrations were examined.

METHODS

This report includes data from (1) a weight loss trial, (2) an evaluation of acute exercise effects on mixed-meal (60% kcal from carbohydrates) tolerance test responses, and (3) a meta-analysis to determine normal fasting adropin concentrations.

RESULTS

Distribution of plasma adropin concentrations exhibited positive skew and kurtosis. The effect of weight loss on plasma adropin concentrations was dependent on baseline plasma adropin concentrations, with an inverse association between baseline and a decline in concentrations after weight loss (Spearman's ρ = -0.575; P < 0.001). When ranked by baseline plasma adropin concentrations, only values in the upper quartile declined with weight loss. Plasma adropin concentrations under the main area of the bell curve correlated negatively with habitual carbohydrate intake and plasma lipids. There was a negative correlation between baseline values and a transient decline in plasma adropin during the mixed-meal tolerance test.

CONCLUSIONS

Plasma adropin concentrations in humans are sensitive to dietary macronutrients, perhaps due to habitual consumption of carbohydrate-rich diets suppressing circulating levels. Very high adropin levels may indicate cardiometabolic conditions sensitive to weight loss.

Potential Roles of Adropin in Central Nervous System: Review of Current Literature

Adropin is a 4.9 kDa peptide that is important for maintenance of metabolic and non-metabolic homeostasis. It regulates glucose and fatty acid metabolism and is involved in endothelial cell function and endothelial nitric oxide (NO) synthase bioactivity as well as physical activity and motor coordination. Adropin is expressed in many tissues and organs including central nervous system (CNS). This peptide plays a crucial role in the development of various CNS disorders such as stroke, schizophrenia, bipolar disorder as well as Alzheimer's, Parkinson's, and Huntington's diseases. In this comprehensive review, the potential roles of adropin in cellular signaling pathways that lead to pathogenesis and/or treatment of CNS disorders will be discussed.

Adropin as a potential marker of enzyme-positive acute coronary syndrome

Aim

Enzyme-positive acute coronary syndrome (EPACS) can cause injury to or death of the heart muscle owing to prolonged ischaemia. Recent research has indicated that in addition to liver and brain cells, cardiomyocytes also produce adropin. We hypothesised that adropin is released into the bloodstream during myocardial injury caused by acute coronary syndrome (ACS), so serum and saliva levels rise as the myocytes die. Therefore, it could be useful to investigate how ACS affects the timing and significance of adropin release in human subjects

Methods

Samples were taken over three days after admission, from 22 EPACS patients and 24 age- and gendermatched controls. The three major salivary glands (submandibular, sublingual and parotid) were immunohistochemically screened for adropin production, and serum and saliva adropin levels were measured by an enzyme-linked immunosorbent assay (ELISA). Salivary gland cells produce and secrete adropin locally.

Results

Serum adropin, troponin I, CK and CK-MB concentrations in the EPACS group became gradually higher than those in the control group up to six hours (p < 0.05), and troponin I continued to rise up to 12 hours after EPACS. The same relative increase in adropin level was observed in the saliva. Troponin I, CK and CK-MB levels started to decrease after 12 hours, while saliva and serum adropin levels started to decrease at six hours after EPACS. In samples taken four hours after EPACS, when the serum adropin value averaged 4.43 ng/ml, the receiver operating characteristic curve showed that the serum adropin concentration indicated EPACS with 91.7% sensitivity and 50% specificity, while when the cut-off adropin value in saliva was 4.12 ng/ml, the saliva adropin concentration indicated EPACS with 91.7% sensitivity and 57% specificity.

Conclusion

In addition to cardiac troponin and CK-MB assays, measurement of adropin level in saliva and serum samples is a potential marker for diagnosing EPACS.

Therapeutic effects of adropin on glucose tolerance and substrate utilization in diet-induced obese mice with insulin resistance

Objective

The peptide hormone adropin regulates fuel selection preferences in skeletal muscle under fed and fasted conditions. Here, we investigated whether adropin treatment can ameliorate the dysregulation of fuel substrate metabolism, and improve aspects of glucose homeostasis in diet-induced obesity (DIO) with insulin resistance.

Methods

DIO C57BL/6 mice maintained on a 60% kcal fat diet received five intraperitoneal (i.p.) injections of the bioactive peptide adropin^34-76 (450 nmol/kg/i.p.). Following treatment, glucose tolerance and whole body insulin sensitivity were assessed and indirect calorimetry was employed to analyze whole body substrate oxidation preferences. Biochemical assays performed in skeletal muscle samples analyzed insulin signaling action and substrate oxidation.

Results

Adropin treatment improved glucose tolerance, enhanced insulin action and augmented metabolic flexibility towards glucose utilization. In muscle, adropin treatment increased insulin-induced Akt phosphorylation and cell-surface expression of GLUT4 suggesting sensitization of insulin signaling pathways. Reduced incomplete fatty acid oxidation and increased CoA/acetyl-CoA ratio suggested improved mitochondrial function. The underlying mechanisms appear to involve suppressions of carnitine palmitoyltransferase-1B (CPT-1B) and CD36, two key enzymes in fatty acid utilization. Adropin treatment activated pyruvate dehydrogenase (PDH), a rate-limiting enzyme in glucose oxidation, and downregulated PDH kinase-4 (PDK-4) that inhibits PDH. Along with these changes, adropin treatment downregulated peroxisome proliferator-activated receptor-gamma coactivator-1α that regulates expression of Cpt1b, Cd36 and Pdk4.

Conclusions

Adropin treatment of DIO mice enhances glucose tolerance, ameliorates insulin resistance and promotes preferential use of carbohydrate over fat in fuel selection. Skeletal muscle is a key organ in mediating adropin's whole-body effects, sensitizing insulin signaling pathways and altering fuel selection preference to favor glucose while suppressing fat oxidation.